Electronics Quiz

Which voltage regulator provides a constant 5V output?

• 7809

• 7812

• 7805

• 7905

Breadboards are mainly used for:

• Permanent connections

• Temporary circuit testing

• High voltage wiring

• Power transmission

Why do we use voltage regulators?

• To amplify current

• To stabilize voltage

• To increase frequency

• To reduce resistance

The first band in a 4-band resistor colour code represents:

• Multiplier

• Tolerance

• First digit

• Last digit

The equivalent resistance of 220Ω and 330Ω in parallel is approximately:

• 550Ω

• 130Ω

• 88Ω

• 200Ω

A touch sensor detects:

• Human touch/contact

• Magnetic field

• Heat

• Sound waves

Combining IR and LDR to trigger a buzzer requires:

• Two microcontrollers

• A logic circuit or Arduino

• An op-amp only

• A transformer

Which of the following is an example of a digital signal?

• Human voice

• Temperature variation in a room

• Binary data in a computer

• Voltage across an analog sensor

A NOT gate inverts:

• Voltage

• Frequency

• Logic level

• Resistance

Which application uses logic gates?

• Burglar alarms

• Voltage regulation

• Power transmission

• Sound amplification